Improving oils.



PATENT OFFICE.

AIMEE M. MOAFEE, OF PORT ARTHUR, TEXAS, ASSIGNOR TO GULF REFINING COMPANY,

OF PITTSBURGH, PENNSYLVANIA, A CORPORATION OF TEXAS.

IMPBOVIN G OILS.

To all whom it may concern:

Be it known that I, ALMER M. McArnn, a citizen of the United States, residing at Port Arthur, in the county of Jefferson and State of Texas, have invented certain new and useful Improvements in Improving Oils, of which the following is a specification.

This invention relates to improving oils;

' and it comprises a method of improving the adapted for aero lane work wherein such cru e gasolene is oiled with a few per cent.

. of aluminum chlorid, vapors of high boiling bodies refluxed and vapors permitted to leave the system at, say, 200 to 250 F. and then condensed; all as more fully hereinafter set forth and as'claimed.

As I have discovered and elsewhere described and 'claimed (Serial No. 792,615) high boiling oils can be converted into gasolene or into gasolene and burning oil by boiling with aluminum chlorid under artial reflux means, the reflux means being a apted to condense and return everything condensable at 350 or 300 F., and vapors having a temperature not higher than that indicated being sent to a suitable condenser. If the temperature of the vapors at the time of access to'the condensing line'be not above about 300 F., all the condensed product will be merchantable gasolene. Whatever the character of the original oil, the condensate will be of saturated character, not needing the usual sulfuric acid treatment to remove unsaturated bodies. If the temperature of the vapors at the time of exit to the condenser be around 350 F., the condensatewill be a material which can be fractionated into gasolene and burning oils. This condensate, likethe former is of saturated character. In another application (Serial No. 1375, January 9, 1915) whereof the present is a continuation of so much as iscommon to the two, I have described this principle as Specification of Letters Patent.

Patented Dec. as, 1919.

Application filed June 26, 1918. Serial No. 242,077.

applied to the improvement of vapors of vanous commercial low boiling oils, such as gasolene and I do not claim hereinsuch vapor treatment.

Gasolene as it comes on the market is partly of the type known as refinery asolene, that is volatile oils naturall contained in crude petroleum and obtaine therefrom by a simple distillation operation. In part, commercial gasolene is obtained by destructive distillation of higher boiling oils; by what is known as cracking. In cracking the oil is heated above 600 F. and undergoesa breaking down with the result of producing low boiling oils of the character of gasolene. Sometimes cracking is under pressure to maintain the oilsdiquid at a higher temperature than would otherwise be possible; and sometimes cracking is done with the ordinary pressure. Whatever the wa of cracking adopted, the product is not 0 as good character as refinery gasolene, being usually unsaturated in its character. Gasolene as marketed, whether cracked gasolene or refinery gasolene, is a non-homogeneous material, with a. wide range of boiling point, a difference of many degrees between its initial and end boiling points. It contains a proportion of very low boiling oils and usually a large proportion of relatively high boiling oils. While the commercial gasolene of course varies, much of it be 'ns to boil at 120 F. and it is not all disti led below 350 F. This is immaterial for most of the uses of gasolene, but for some types of engine, and particularly those employed in aeroplanes, a more homogeneous material is desired.

In the present invention it is one of my objects to convert commercial gasolene into a material of higher quality, both as regards homogeneity and in other respects. The

600 F., the mixture with about er cent. of aluminum chlorid enters into e ullition with suflicient evolution of'vapors for distillation at about 500 to 550 F., the particular temperature depending partly on the oil and partly on the proportion of the aluminum chlorid-and the degree of activ- Y ity of the chlorid.

boiling portions are converted into lower boiling and the condensate as a whole may be of any desired narrow boiling range. It will also be of saturated character whatever that of the original gasolene. The saturating effect alone may be obtained by simply warming the gasolene with aluminum chlorid at, say, 120 F. to 150, stirring vigorously. Some portion of the gasolene being volatile at these temperatures, in this operation a reflux condenser is used to prevent escape of vapors from the system and return them to the action of the chlorid. On cooling and allowing the gasolene to become quiescent, most of the aluminum chlorid will deposit out as a heavy sludge which may be-easily removed. Cooling may be whenever the desired degree of saturation (as indicated'by the iodin test) is attained. The gasolene may be freed of any residual suspended or dissolved aluminum chlorid by redistillation or by treatment with a little sulfuric acid. The aluminum chlorid sludge may be used for a preliminary treatme'nt of another charge in order to exhaust its activity, the treatment of this second charge being then continued with fresh chlorid. The gasolene obtained in operating at these low temperatures will be, in boiling oint and distilling characteristics, much ike the original but it will differ therefrom in that it requres no treatment with sulfuric acid to remove unsaturated compounds.

By a modification of the described method I may also materially improve the quality of these cracked gasolenes in other respects than the conversion of the unsaturated into the saturated hydrocarbons. There is a demand for gasolene distilling within a narrower temperature range than that of ordinary gasolene which, as it now occurs on the market, may begin to distil at 120 F. and end at a distilli temperature of 350 F. In so doing I ta e advantage not only of the property of aluminum chlorid of converting unsaturated into saturated bodies, but also of its property of converting higher boiling oils into lower boiling. For this purpose I operate at a somewhat higher temperature in treating the mixture of gasolene and aluminum chlorid than that just described. This higher temperature produces more or less distillation and I control this distillation in a special way. This treatment may not only be ap lied to the commercial cracked gasolenes ut also to the cracked distillates from which these cracked gasolenes are made by redistillation. These cracked distillates begin to boil at about 120 F. and have a final boiling point of about 500 F., or possibly above. To this end I mix the materlal with aluminum chlorid as before and heat to the boiling temperature of the mixture under such conditions as will permit a refluxing of vapors of high boiling, or heavy, portions or fractions. The vapors may be allowed to pass to the final condensing system at a temperature between 150 F. and 250 F. A temperature of 200 F. is sometimes used. The product here is, as before, a clean sweet gasolene but it is of more uniform characteristics than the original, having a closer distillation range.

In a specific embodiment of the present invention any commercial grade of gasolene is charged together with some anhydrous aluminum chlorid into a suitable still provided with stirring means. As a rule about 5.per cent. of fresh aluminum chlorid is a desirable proportion. Aluminum chlorid which has been used in other methods of treating oil until its activity is partially exhausted may be employed herebut in this event the proportion employe is concomitantly larger. The still should be provided with reflux means and the operation so conducted that the vapors passing thereflux means emerge, say, 150 to 250 I By conducting the firing or heating to give vigorous ebullition of the mixture of gasolene and aluminum chlorid, a chemical ac tion takes place and the asolene will be converted into a highly vo atile product of uniform nature and completely saturated character. All, or substantially all, of the gasolene will be converted into this. homogeneous product. If the temperature of the vapors at the point of exit be held at about 200 F. all the product will be of this character. If the temperature be held somewhat higher, say 250 F., the distillate may need rectification. In this event residues from the rectification may be re-submitted to the process or sold as burning oil of high quality.

A similar operation may be erformed on kerosene or burning 011 of ow grade with the production of high grade kerosene' of substantially uniform character. In so treating kerosene there is generally the production of more or less gasolene which is separated from'the distillate by suitable distillation.

The gasolene used should be dry and as free from sulfur as possible; Both moisture and sulfur tend to exhaust the activity of the aluminum chlorid uselessly. The operation may be performed in apparatus of any of the common materials, such as iron and steel. The aluminum chlorid used should be anhydrous, the hydrated aluminum chlorid not being effective for the present purposes.

This application is a continuation in part of my copending application Serial No. 1375, filed January 9, 1915.

-What I claim is v 1. In the manufacture of high grade gasolene, the process which comprises subjecting cracked gasolene at a temperature below its end boiling point to the action of aluminum .chloridin suflicient amount to convert uncompounds into low boiling saturated compounds.

ing from such boiling operation while condensing vapors of lower boiling point and continuing the operation until the gasolene is distilled over as a gasolene of a narrower range of boiling points.

5. The process of homogenizing gasolene which comprises boiling with aluminum chlorid a commercial gasolene having constituents higher boiling than 250 F., cooling the vapors to a temperature not above 250 F. and, returning the condensate for renewed action by aluminum chlorid, condensin vapors passing over at a temperature be ow 250 F. and continuing the operation until substantially all of the original gasolene is converted into a distillate free of the higher boiling constituents.

In testimony whereof, I afiix my signature hereto.

ALMER M. McAFEE.

refluxing the more condensable vapors arise 

